A high-capacity hexaazatrinaphthylene anode for aqueous organic hybrid flow batteries

Abstract

By using a microwave assisted Schiff-base condensation reaction between triquinoyl and 1,2-diaminobenzene, we synthesize a water-insoluble fused phenazine derivative, hexaazatrinaphtylene (HATN), and study its electrochemical performance against a K₄[Fe(CN)₆]/K₃[Fe(CN)₆] catholyte in an alkaline aqueous hybrid flow battery. Reversible two-step three-electron transfers and rapid surface-controlled redox reaction kinetics are observed for the HATN electrode in alkaline aqueous solution. Compared to previously reported organic anode materials for aqueous hybrid flow batteries, HATN exhibits greatly enhanced specific capacity and comparable efficiency and cycling stability.